Dressing



July 28, 1970 J. H. GARDNER ETAL '73,521,631

DRESSING Filed Nov. 8. 1967 INVENTORS.

ATTORNEY 3,521,631 DRESSING Jack H. Gardner, Highland Park, and David T.Rovee,`

U.S. Cl. 128-156 16 Claims ABSTRACT OF THE DISCLOSURE An occlusivedressing for wounds, the dressing comprising an impervious flexible fihnadapted to contact and cover the area of the wound, an absorbent padbacking the wound-contacting film and extending beyond a substantialportion of the periphery of the impervious film and a flexibleimperforate fllrn backing extending beyond the edges of both theWound-contacting film and the absorbent pad. At least the portion of thefilm backing which extends beyond the outside edges of thewoundcontacting film and absorbent pad contains a pressuresensitiveadhesive coating for securing the same to the skin of a patient aroundthe edges of the absorbent pad and wound-contacting film so as tocompletely enclose the same when the dressing is applied. The absorbentpad extending beyond the edges of the wound-contacting film removeswound exudate from the proximate area of the wound without the padcoming in contact with the open wound itself.

BRIEF SUMMARY OF THE INVENTION It has heretofore been proposed toutilize a smooth, flexible sheet in Contact with a wound surface in thetreatment of wounds as the healing wound tissue will generally notadhere to such smooth surfaces. Thus, both thin metal sheets and organicfilms have been proposed for this purpose. However, because of the needfor removing wound exudate, these protective film coverings have beenperforated or cut to permit wound exudate to pass therethrough to abacking absorbent. This perforating of the film, however, has exposedthe fibrous backing absorbent with the result that some Wound adherenceoccurs in these exposed areas. If the perforations in thewound-contacting film are made too small, then Wound exudate soon plugsthe openings with the result that the exudate cannot be picked up by thebacking absorbent.'

This causes puddling to occur under the film, forming pockets of woundexudate which tends to push the film up away from the wound surface.Such pockets of wound exudate provide an excellent environment forbacteria proliferation and should be avoided where possible. Recent workhas shown that there is a tendency for Wounds to heal more rapidly ifthe dressing used is occlusive in nature, i.e., if it either prevents orsubstantially inhibits the escape of moisture from the wound area(Nature, Dec. 216, 1963. Biology-Effect of Air Exposure and Occlusion onExperimental Human Skin Wounds, pp. 377- 379).

The present invention combines the advantages of the wound release ofcontinuous film dressings and the more rapid healing of occlusive filmdressings Iwhile avoiding some of the disadvantages. In accordance withthe present invention there is prepared a dressing in which thewound-contacting surface is a flexible imperforate sheet, the same beingdesigned to cover the Wound area so that edge portions of the flexibleWound-contacting sheet are relatively close to an open Wound whenapplied to the same. The flexible wound-contacting sheet is backed by anabsorbent pad which extends appreciably beyond such edges of thewound-contacting flexible sheet, the absorb- Patent 3,521,63 l PatentedJuly 28, 1970 ent pad acting to draw off Iwound exudate from the edgesof the wound-contacting sheet. The wound exudate is thus not permittedto build up in the area between the wound and the Wound-contacting sheetwith the result that the wound and wound-contacting sheet are kept inintimate contact. A substantially impervious backing 'film is providedwhich extends beyond the edges of both the flexible wound-contactingsheet and absorbent pad to completely cover the same when the dressingis applied to a patient. The border of this backing film preferablycontains adhesive whereby the'same is adhesively-secured to theunderlying skin to occlude the entire dressing. The extending border ofthe backing film may, however, be secured in place through the use ofadhesive tape if desired.

DETAILED DESCRIPTION OF THE INVENTION The invention is more readilydescribed by reference to the drawings which show certain embodiments ofthe same. The embodiments illustrated in the drawings, however, are forpurpose of illustration only and the invention is not limited solely tothe specific embodiments shown.

Referring to the drawings:

FIG. v1 is a bottom plan view of a dressing made in accordance with thepresent invention;

FIG. 2 is a cross-sectional view of the dressing of FIG. 1 taken alongline 2 2;

FIG. 3 is the dressing ofFIGS. 1 and 2 with the protective facing stillon prior to removal;

FIG. 4 is a different modification of a dressing made in accordance withthe present invention;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 4.

Referring to FIG. 1, the occlusive dressing there illustrated has aflexible sheet 10 adapted to contact the wound surface when the dressingis in place. The flexible sheet 10\ is hereinafter referred to as thewound-contacting portion of the dressing. The Wound-contacting portionor flexible sheet 10, is so formed that no part thereof is more than0.75 inch distance from an edge 13 of the sheet 10. In the particulardressing illustrated in FIG. l the wound-contacting flexible sheet 10has somewhat the shape of a cross with arms 11 and center circularimperforate wound cover portion 12. The area of sheet 10 of furthestdistance from an edge 13 is the area situated in the exact center of thecircular wound cover portion 12. Thus the dimensions of thewound-contacting sheet 10 should be such that the diameter of thecircular portion 12 not be greater than 1.5 inches.

The sheet 10 may be formed of any of the flexible materials known to berelatively nonadhering to healing wound surfaces and inert to the same.The preferred flexible sheet materials for the wound-contacting portion10 are organic polymer films such, for example, as polyethylene,polypropylene, Mylar, polyvinyl chloride, Saran films, ethylene-vinylacetate copolymer, and nylon.

An absorbent 14 in the form of a pad is placed back of sheet 10 andextends beyond the edge 13 of the same. The absorbent pad 14 may extendbeyond the entire edge 13 of the wound-contacting sheet 10' or onlybeyond a portion thereof as occurs in the specific embodimentillustrated wherein it extends beyond most of the edge portion with apart of the edge, such as illustrated at 13', not being backed by theabsorbent. The exposed portion 15 of the absorbent, however, should besufficient to provide a substantial amount of absorbent extending beyondmost of the peripheral edge -13 of the woundcontacting film sopositioned with respect to the film 12 that at least a portion thereofis within about 0.75 inch distance of any area within thewound-contacting film 10. By this construction there is a minimumdistance for wound exudate to travel before contact with absorbent whichrapidly removes the exudate from the peripheral edge of thewound-contacting flexible sheet 10, thus preventing buildup of exudateunder the film with formation of pockets of exudate.

The wound-contacting flexible sheet 10 and the absorbent 14 are backedby an imperforate flexible sheet 16 which is sufiiciently large toextend beyond the peripheral edges of both the wound-contacting flexiblesheet 10 and the backing absorbent 14.

The fiexible backing sheet 16 may be formed of any exible organicfilm-forming material and is adapted to be secured around its edges 17to the skin of a patient after the dressing is placed over a wound. Thissecuring of the edges 17 may be done by taping along the edges 17 of thebacking film 16 but in the preferred construction is done by means ofpressure-sensitive adhesive 18 which may be coated over the entiresurface of film 16 as in the particular embodiment illustrated in FIGS.1 through 3, or may be placed only around the peripheral edge 18 of thebacking film to form an adhesive border for sealing the same to the skinof the patient.

This backing film 16 is relatively impervious to moisture and forms anocclusive environment under the same which environment, as previouslyindicated, is beneficial from the standpoint of promoting more rapidhealing of the wound.

The absorbent 14 should wet readily and rapidly so that any woundexudate which contacts the same from the edge 13 is rapidly drawn awayand dispersed in the absorbent. The absorbent 14 is preferably in theform of a cushioning pad which may be formed of fibers, such asccllulosic fibers bonded together either mechanically or through the useof bonding agents to give a resilient absorbent body. The absorbent 14may also be in the form of a hydrophilic cellular resin sheet such asfoamed polyurethane formed of wettable or hydrophilic polyurethaneresin.

Although in FIGS. 1 and 2 the dressing is shown without any protectivecovering for the pressure-sensitive adhesive coating 18 the dressing,prior to application, is provided rwith protective cover facings 19 and20, as illustrated in FIG. 3. These protective facings are removed priorto application of the dressing. Protective facings 19 and .20 extendover both the adhesive edge portion 17 and over the centerIwound-contacting flexible sheet portion 10 to protect the same inhandling prior to application of the dressing. When the dressing is tobe applied, tabs 21 and 22 are grasped and the protective sheets 19 and20 removed by pulling the tabs away from each other. The protectivefacings 19 and 20 may be formed of any of the conventional protectivefacing materials used, for example, in the preparation of adhesivebandages.

The dressing illustrated in FIGS. l through 3 is designed primarily forthe treatment of relatively small wounds. In FIGS. 4 and 5 isillustrated a dressing designed for treatment of relatively large longWounds of the incision type. In the dressing of FIGS. 4 and 5 thewoundcontacting flexible sheet 21 is designed so as to have scallopededges 22 with the scallops 24 extending Well towards the centerlongitudinal axis 23 of the flexible sheet 21. The fiexible sheet 21 hasappreciable length in its lengthwise direction so that the same containsa relatively long imperforate wound cover portion that will coverrelatively long incisions without any portion of the incision extendingbeyond the edge 22 in the scallops 24 of the fiexible wound-contactingsheet 21. It will be noted that the relatively deep scallops 24 alongthe edges 22 of the flexible sheet 21 provide a construction in whichthere is no area of the wound cover portion of flexible sheet 21 whichis more than 0.75 inch from an edge thereof beyond which extends aportion of absorbent 25.

The flexible wound-contacting sheet 21 is backed by an absorbent pad 25in a manner similar to that of the dressing of FIGS. l through 3. Theabsorbent p-ad 25 of the dressing of FIGS. 4 and 5, however, isrectangular in shape and its dimensions are such that pad 25 extendsbeyond the peripheral edge 22 of most of the fiexible wound-contactingsheet 21. Thus, at no point in the dressing is there a distance of morethan 0.75 inch from an area of the iiexible wound-contacting sheet 21 toa peripheral edge beyond which the absorbent 25 extends. Although in theparticular embodiment illustrated the edge portions 26 between thescallops 24 are shown as extending beyond the absorbent '25, suchconstruction is only for aiding in the manufacture of the particulardressing embodiments illustrated. These extending end portions 26,indicated as 13 in FIGS. l through 13', are for the purpose of helpingto hold all of the parts of the dressing in a single unitary dressingconstruction. In constructions of dressings illustrated these extendingend portions of the facing film are anchored to the adhesive of thebacking film. This flexible backing film 27, in FIGS. 4 and 5, is alsoof rectangular shape, the same being larger than the absorbent pad 25 soas to provide a peripheral edge 28 which extends beyond both theperipheral edge of the absorbent 25 and all edges of thewound-contacting exible sheet 21. The backing 27 has apressure-sensitive adhesive coating 29 on one side thereof which servesto adhere the edge 28 of the dressing to the skin of a patient rwhen thesame is applied over a wound. The extending tabs 13', for example, inFIGS. l, 2 and 3, and 26 in FIGS. 4 and 5 are adhered to thispressure-sensitive adhesive coating, thus securing the flexiblewound-contacting sheet to the fiexible backing sheet. If desired,however, the absorbent, such as absorbent 25 of FIGS. 4 and 5, couldextend beyond all edges of the flexible woundcontacting film 21, thesame then being secured to the absorbent through an adhesive coatingapplied to the interface between the absorbent 25 and the flexibleWoundcontacting film 21. The preferred construction, however, is thatillustrated in the particular embodiments shown in the drawings.

Although, in the dressing embodiment as illustrated in FIGS. 4 and 5,there is no protective covering shown for the pressure-sensitiveadhesive 29, protective facings similar to that illustrated in FIG. 3may be used.

The backing film 27 of the dressing of FIGS. 4 and 5 is similar to thatof the dressing of FIGS. 1 through 3, the same being formed of flexible,organic polymer film material. The adhesive coating 29 may be spreadover the entire surface of the backing 27 or only around the peripheraledge to give an adhesive border. As previously indicated, in thedescription of the dressing of FIGS. 1 through 3, however, thepressure-sensitive adhesive border could be dispensed with and thedressing applied and secured in place through the use ofpressure-sensitive adhesive tape applied along the edge for securing thesame and sealing the edges of the dressing to the underlying skin of apatient. However, in the preferred practice the dressing is providedwith the pressure-sensitive adhesive at least around the peripheral edgeof the backing film 27 to provide a seal and secure the dressing inplace.

Certain specific embodiments have been utilized in illustrating thepresent invention. The invention, however, is not limited to thesespecific embodiments and may be practiced in the form of otherembodiments which would be apparent to one skilled in the art afterhaving the advantage of the teaching of the present specification. Theinvention, accordingly, is not to be limited except by the appendedclaims.

Having thus described our invention, we claim:

1. A surgical dressing comprising a flexible sheet having a permanentlyimperforate wound cover portion adapted to be placed in contact with andcover a wound and remain imperforate while on said wound surface, anabsorbent for wound exudate, and a fiexible imperforate film backing,said absorbent being positioned between said fiexible backing and saidflexible sheet having said imperforate wound cover portion and extendingbeyond at least a portion of the edge of said flexible sheet there beingno area in said mperforate Wound cover portion of said flexible sheetgreater in distance than 0.75 inch from an edge of said ilexible sheetbeyond which said absorbent extends and said backing extending beyondthe edges of said flexible sheet and said absorbent to provide a borderextending around said dressing for securing said dressing to the skin ofa patient.

2. A dressing of claim 1 in which said border extending around saiddressing is an adhesive border.

3. A dressing of claim 2 in which said border contains apressure-sensitive adhesive coating.

4. A dressing of claim 1 in Iwhich said flexible sheet contains aplurality of tabs, extending outwardly from said imperforate wound coverportion the ends of said tabs being secured to said flexible backing.

5. A dressing of claim 4 in which said flexible backing is coated with apressure-sensitive adhesive and the ends of said tabs are adhesivelysecured thereto.

6. A dressing of claim 1 in which said imperforate Wound cover portionis substantially circular in shape with a diameter not exceeding 11/2inch.

7. A dressing of claim 6 in which said border extending around saiddressing is an adhesive border.

8. A dressing of claim 7 in which said border contains apressure-sensitive adhesive coating.

9. A dressing of claim 8 in which said flexible sheet contains aplurality of tabs, extending outwardly from said imperforate wound coverportion the ends of said tabs being secured to said exible backing.

10. A dressing of claim 9 in which said exi'ble backing is coated with apressure-sensitive adhesive and the ends of said tabs are adhesivelysecured thereto.

11. A dressing of claim 1 in which said imperforate wound cover portionhas a length appreciably greater than its width.

12. A dressing of claim 11 in which said border extending around saiddressing is an adhesive border.

13. A dressing of claim 12 in which said border contains apressure-sensitive adhesive coating.

14. A dressing of claim 13 in which said flexible sheet contains aplurality of tabs, extending outwardly from said imperforate Wound coverportion the ends of said tabs being secured to said flexible backing.

15. A dressing of claim 14 in which said exible backing is coated with apressure-sensitive adhesive and the ends of said tabs are adhesivelysecured thereto.

16. A dressing of claim 14 in which the edge of said flexible sheet isscalloped to form said tabs the inner p0rtion of the scallops definingthe general area of said imperforate wound cover portion.

References Cited UNITED STATES PATENTS L. W. TRAPP, Primary Examiner

